The remedy of specific performance enables a court having equitable powers to compel a party to a contract to perform, if not exactly at least substantially, what he has undertaken to do. Save where a defendant's obligation is negative a threatened breach of contract rarely affords ground for judicial action,1 so that affirmative performance enforced by the court must almost invariably take place at a later day than the contract required. From comparatively early times the English chancellors gave this redress.2 Equity requires generally that a contract in order to be specifically enforceable shall be capable of enforcement in a court of law. That is, the requisites of a contract are the same in equity as at law. Where an exception is made to this principle, as in enforcing contracts for the sale of land where .the Statute of Frauds has not been satisfied,3 or in enforcing voluntary promises to convey land on which the promisee has made improvements/ the interposition of equity is said to be due to its desire to prevent a fraud. It may be observed, however, that there are many cases where a plaintiff who has relied to his injury on a gratuitous promise of the defendant, even though it be one relating to land, can get no relief. If it be assumed, then, that a valid contract exists and has been broken, the general rule defining the instances where specific performance will be granted is - where damages are an inadequate remedy and the nature of the contract is such that specific enforcement of it will not involve too great practical difficulties, equity will grant a decree of specific performance. The fact that there is a remedy at law does not preclude the equitable remedy.5 The applications of this prin-

1 Bills for instructions by trustees prior to any action taken by or against them have been common, but similar relief though in the nature of the case equally possible has not been common with regards to contracts; but now by statute in England a person interested in a contract may not only seek its interpretation from the court, but may seek a binding declaration of his right. This useful extension of remedial justice will doubtless become mote common in the United States.

2 With one exception (Cokayn v. Hurst, 10 Selden Soc. No. 142) the earliest clear instances discovered by Ames are reported in the reign of Elisabeth. See Lectures on Legal History, 248; 1 Green Bag, 26; Gas. Eq. Jut. 37, n.

3 See supra, (494.

4 See supra, (139.

5 In order to deny one the relief ciple are not, however, always free from technicality. In the course of centuries, rules of equity tend to become rigid, and like rules of law do not always yield readily when reason makes it desirable. There is, however, a distinct tendency in modern times to extend the remedy where justice requires it. The converse statement, that any contract which is valid at law is also enforceable in equity if its subject-matter is appropriate for that jurisdiction, is generally true, but subject to the exception that equity reserves a discretion in granting its relief; 6 and to one rule that is laid down perhaps too positively, namely, that equity will not grant specific performance of a contract unsupported by valuable consideration even though under seal.7